Andrzej Lebioda

PSA bounces after brachytherapy HDR and external beam radiation therapy for prostate cancer

Summary Background The serum prostate-specific antigen (PSA) test is the most commonly used method for confirming response of prostate cancer after definitive radiation therapy (RT). PSA levels are expected to decrease after radiotherapy but usually remain detectable. Three consecutive PSA rises above the post-treatment nadir have been defined as biochemical failure by the ASTRO consensus panel [1]. Rising serum PSA concentration after RT does not always indicate treatment failure. Some patients have a temporary PSA spike, usually within 12–30 months of radiation therapy [2–4]. Most PSA bounces have a magnitude of 1.0 ng/mL or less. This observation was first described by Wallner and colleagues in 1997 [5]. Although this phenomenon is a source of anxiety for both the patient and the physician, its relevance to biochemical failure is controversial. Aim To determine the clinical and dosimetric factors that predict prostate-specific antigen (PSA) bouncing following brachytherapy HDR and three-dimensional conformal radiation therapy (3D-CRT) for prostate cancer patients. Materials/Methods The evaluated population consisted of 71 hormone-naive patients with a minimum of 2 years of follow-up and at least 6 post-treatment PSA levels. All patients were treated using 3D-CRT combined with brachytherapy HDR. A bounce was defined as a PSA rise of ≥0.2 ng/mL above the nadir followed by a subsequent 120 decline of ≥0.2 ng/mL. Clinical factors evaluated included: patient age, Gleason score, maximum initial pretreatment PSA value (iPSAmax), clinical stage, prostate volume, median time to PSA nadir, median PSA nadir value and patient follow-up in months. Dosimetric factors evaluated included the percentage of the prostate volume receiving 100% (V100), 150% (V150) and 200% (V200) of the prescribed minimal peripheral dose. Results Statistically significant predictive factors for PSA bounce were age, V100, V150, V200, iPSAmax and median time to PSA nadir. Logistic regression model for multivariate analysis revealed that only age, iPSAmax and V200 were statistically significant predictors for PSA bounce. There were no statistical differences between median nadir among patients who exhibited a PSA bounce and those who did not, but non-bouncers reached PSA nadir earlier than bouncers; median time was 12.1 vs 17.2 months respectively. Conclusion PSA bouncing occurs in approximately one third (1/3) of patients treated with 3D-CRT and brachytherapy HDR. Bouncing is associated with age, higher pretreatment PSA level and increased V200 factor.

Results of interstitial HDR brachytherapy for cancer of the lower lip

Summary Background HDR brachytherapy has been employed in the treatment of cancers in numerous locations around the body, however, few publications have dealt with primary carcinomas of the head and neck. To our knowledge, only one paper concerns the use of this technique in the treatment of cancers of the lower lip. Furthermore, the recommendations given by the American Association of Brachytherapy do not appear to elaborate on the subject. Aim To analyse the treatment of lower lip carcinoma by interstitial HDR brachytherapy. Materials/Methods Retrospective analysis of the results of treatment was carried out among a group of 24 consecutive patients, of whom 18 were treated by brachytherapy alone while 6 others were treated after surgery. Fifteen patients were classified as T1, nine patients as T2. 23 patients were classified as N0 and one as N1. Each patient had histologically confirmed squamous cell carcinoma. Radiotherapy involved interstitial, high dose rate brachytherapy with an iridium-192 source. Post-operative brachytherapy was indicated in cases of microscopically incomplete excision. The dose was determined using the Paris method, the reference dose being 80% or at a point 3–5 mm from the macroscopic lesion or tumour bed. The mean total dose was 35 Gy, the mean number of fractions was 7, and the mean fraction dose was 5.7 Gy. The total treatment time was 12 days, on average, whereas the mean follow-up was 32 months. Results Local control was obtained after 24 months in 21 patients (87.5%). All patients developed a severe early reaction. Three patients with mouth corner infiltration (100%) failed to show complete regression. Two of these patients underwent additional irradiation to the residual lesion, resulting in cures. The third patient underwent successful surgical treatment. The cosmetic and functional effect was very good. Conclusuions Interstitial HDR brachytherapy is an effective and safe method for the treatment of carcinoma in the lower lip.

Tumour surface area as a prognostic factor in primary and recurrent glioblastoma irradiated with 192Ir implantation

Summary Background To evaluate the impact of tumour surface area (TSA) on survival of patients treated with 192 Ir implantation for glioblastoma multiforme (GBM). Methods/Materials The analysis of survival and prognostic factors was performed based on a retrospective study group of 120 patients (74 males and 46 females; mean age 53 years; mean KPS score 74.6) irradiated with 192 Ir for GBM between 1999 and 2003. There were 72 (60%) patients with recurrent and 48 (40%) with primary inoperable tumour. Patients with recurrences were initially treated with surgery and external beam radiotherapy (EBRT; mean total dose (MTD) 53.5Gy). Individuals with primary inoperable glioblastoma underwent EBRT (MTD 37.2Gy) after brachytherapy completion. All patients were irradiated with 192 Ir with a total dose of 15Gy given in 5 fractions. Results For the total group of patients 1-year and 2-year survival were 22% and 11%, respectively, with a median survival time (MST) of 6.1 months. The multivariate Cox analysis of the best fit (Chi 2 =22.98, p=0.000041) distinguished such variables as: patient age (p=0.002), performance status (p=0.04) and tumour surface area (p=0.04) to significantly affect survival. Patients with TSA 2 had better prognosis compared to those with TSA≥90cm 2 (p Conclusions Tumour surface area is an independent prognostic factor in patients irradiated with 192 Ir for glioblastoma multiforme. TSA less than 90cm 2 predicts significantly longer survival and appears to be a more powerful prognostic variable than tumour volume.

Rectovaginal fistula risk doses in patients with cervical cancer

Summary Purpose To evaluate the incidence and risk factors, both clinical and physical, of the development of a postradiation recto-vaginal fistula in cervical cancer patients. Materials and methods A retrospective analysis of 222 consecutive patients receiving radical treatment for invasive cervical cancer at the Regional Oncology Centre in Bydgoszcz between 1993 and 1995 has been performed, on 140 patients treated with radiotherapy alone and 82 patients who received radiotherapy combined with surgical treatment. The doses and dose rates of brachytherapy were specified at point A, the mean dose being 49 and 46 Gy for radiotherapy alone and combined treatment, respectively. External beam irradiation was applied in fractions of 1.8–2 Gy, up to a total dose of 44.6 Gy (36–50 Gy). The dose and dose rate in the rectum (point R 1 ) were determined according to the protocol 38th ICRU, the biological extrapolated dose (BED), using a LQ model, was calculated as a sum of a dose from external beam irradiation and brachytherapy. Results A total of 17 (7.6%) recto-vaginal cases of fistulae were found; 13 (9,2%) in patients treated with radiotherapy alone, 4 (4,8%) in patients treated with combined treatment. The median latency time was 11.8 months (range 7 to 24). There is a strong association between the risk of developing a fistula and the biological extrapolated dose (BED) at point R 1 . Addition of surgical treatment results in a higher risk of complications. Age, clinical stage, hemoglobin level, performance status and the overall treatment time, type and size of applicators were not found to have a significant effect on the risk of developing recto-vaginal fistula. Conclusions The biological extrapolated dose (BED) at point R 1 is an important predictive factor relevant for postradiotherapeutic rectovaginal fistula incidence risk. Surgery is an important factor modifying the postradiotherapeutic rectovaginal fistula incidence risk. No significant influence on the fistula incidence risk of such parameters as age, FIGO stage, physical activity, haemoglobin level, overall treatment time, type and size of applicators has been demonstrated.

Estimation of the α/β ratio for lower lip cancer treated with interstitial HDR brachytherapy

Summary Background A standard linear-quadratic (LQ) model is now routinely used for clinical data analysis and the prediction of the clinical effect of radiotherapy. The typical α/β values suggested in the literature range from 10 to 20Gy for most tumours and early responding normal tissues, and from 2 to 5Gy for late responding tissues. Aim The estimation of α/β ratio values for planoepithelial lower lip cancer. Materials/Methods The clinical material is based on the records of 25 patients undergoing radical treatment with interstitial brachytherapy: 19 patients were administered brachytherapy exclusively and 6 patients were treated postoperatively. The following stage arrangement was applied: T 1 in 15 pts, T 2 in 9 pts, N 0 in 24 pts and N 1 only in one T 2 patient. Radiotherapy was based on HDR brachytherapy using the interstitial technique. Patients with positive margins after surgery were qualified for postoperative brachytherapy. The dose was either specified at the reference 80% isodose according to the Paris System or points calculated 3-5 mm from the macroscopic tumour. The average total dose was 38.3Gy, the number of fractions being 7 and the fraction dose 5.3Gy. The overall treatment time was 12 days. The average follow-up period was 30 months. A standard probit regression in conjunction with a linear-quadratic model was used. Results The estimated value of the α/β ratio for lip cancer was 12Gy (±3.72 * 10 −10 95% CI). Conclusions The estimated α/β ratio is consistent with α/β ratios published for squamous cell head and neck cancers.

An analysis of outcomes, after re-irradiation by HDR (high-dose-rate) brachytherapy, among patients with locally recurrent nasopharyngeal carcinoma (NPC)☆

Summary Background Despite aggressive treatment with radiotherapy, which is often combined with chemotherapy, local persistence occurs in 18–40% of patients with nasopharyngeal carcinoma. Brachytherapy is one of the methods for the re-treatment of patients with locally recurrent nasopharyngeal carcinoma. Aim The aim of this paper was to evaluate the effectiveness of HDR (high-dose-rate) treatment of patients with locally recurrent nasopharyngeal carcinoma. Materials/Methods The study took the form of a retrospective analysis and included a group of 28 patients treated in the Brachytherapy Department of the Oncology Centre in Bydgoszcz during the years 1995–2000. Brachytherapy was carried out using a Rotterdam applicator and the MicroSelectron HDR apparatus produced by Nucletron. Irradiation was based on doses of 36 Gy, i.e. 6 Gy applied once a week, and 51 Gy i.e. 3 Gy applied twice a week. This paper presents recovery probability, overall survival and recurrence-free survival within the analysed group of patients. Results The results obtained prove intracavitary HDR (high-dose-rate) brachytherapy to be a viable method for the treatment of patients with recurring nasopharyngeal carcinoma. Conclusions The higher the total dose applied by means of brachytherapy, the greater the chance of locally successful treatment, moreover, the time that elapses before recurrence is considered to be an important factor influencing recurrence-free survival time.

Wpływ optymalizacji geometrycznej na wybrane parametry rozkładu dawki na przykładzie brachyterapii u chorych na raka gruczołu piersiowego

Streszczenie Cel pracy Analiza parametrow rozkladu dawki dla dwuplaszczyznowych implantow w gruczole piersiowym z zastosowaniem optymalizacji geometrycznej. Material i metoda Analizie poddano parametry rozkladu dawki oraz indeks jakości rozkladu dawki QI dla 20 dwuplaszczyznowych aplikacji wykonanych w naszej praktyce klinicznej. Wyznaczono nastepujące parametry: objetośc referencyjną V 100 , objetośc napromienianą V 50 , objetośc wysokiej dawki V 200 . Parametry te analizowano w przypadku zastosowania optymalizacji geometrycznej rozkladu dawki i bez optymalizacji. Wnioski Optymalizacja geometryczna powoduje wzrost objetości referencyjnej V 100 . W porownaniu z klasycznym implantem nieoptymalizowanym, zgodnym z zasadami systemu Paryskiego brachyterapii wewnątrztkankowej, optymalizacja ta pozwala ograniczyc dlugośc aktywną implantu i nie rozszerzac jej poza obszar targetu. Jest to korzystne w przypadku implantow piersi, gdzie obszar targetu graniczy ze skorą.

Evaluation of brain edema formation defined by MRI after LINAC-based stereotactic radiosurgery

Abstract Background Peri-lesional edema is a serious and well-known complication of stereotactic radiosurgery (SRS). Here we evaluated edema risk after SRS and assessed its formation and resolution dynamics. Patients and methods 107 patients underwent SRS for heterogeneous diagnoses: 34 (29%) with arteriovenous malformations, 38 (35%) with meningiomas, 16 (15%) with metastatic tumors, 16 (15%) with acoustic neuromas, 3 with (3%) cavernomas, and 2 (2%) each with anaplastic astrocytomas and anaplastic oligoastrocytomas. Edema area was delineated in MRI T2-FLAIR sequences 0, 6, 12, 18, 24, 30, and 38 months after treatment. Lesion location was defined as either above (n = 80) or below (n = 32) the “Frankfurt modified line” (FML). Results 17% of patients developed or had worsening post-treatment edema. Edema volume was maximal at 6 months (mean 7.2, SD 1.2) post radiosurgery. Post-SRS edema was 5.1 (1.06 – 24.53) times more likely in patients with lesions above the FML. There was no association between edema development and age, PTV size, number of beams, and diagnosis (p = 0.07). Conclusions Radiosurgery-associated edema develops within 6 months of treatment and decreases over time. Edema occurrence is strongly related to lesion location, and its presence is much more likely when the treated lesions are situated above the Frankfurt line.

Preliminary results of linac-based radiosurgery in arteriovenous malformations and cerebral tumours in the Oncology Centre in Bydgoszcz

Aim of the study Efficacy of stereotactic radiosurgery (SRS) in the treatment in cerebral AVMs, mennigiomas, metastases, acoustic neuromas and recurrent anaplastic gliomas is well documented. The object of this work was the analysis of the results of the treatment of AVM and selected cerebral lesions with linear accelerator-based stereotactic radiosurgery. Material and methods The lesions included: 12 AVMs, 2 cavernomas, 27 meningiomas, 16 metastases, 5 acoustic neuromas, 16 gliomas in 78 patients. A mean radiation dose of 16Gy was delivered to the tumour or AVM margin and 12Gy to the tumours located in a ponto-cerebellar angle. Follow-up was 18 months. Results Control of tumour growth or AVM was achieved in all cases after 6 months and radiological regression was observed in 20 cases after 12 months. The best results were noted in AVMs, meningiomas and neuromas.There were no new permanent deficits nor complications after radiosurgery requiring medicamentation. Conclusions Organization of SRS in Oncological Center in Bydgoszcz involving close co-operation of radiotherapist, neurosurgeon and physicist in the process of qualification and treatment planning is based on the best global standards. Preliminary results of treatment are consistent with the literature data. A longer follow-up is required to determine the long term efficacy and the toxicity of this treatment in our institution.

Clinical Investigations Original article Interstitial brachytherapy for penile cancer: the experience of Oncology Centre in Bydgoszcz

Purpose The aim of this work was to analyze the treatment results and complications of patients with penile cancer treated in our centre. Material and methods Thirty three patients were included in this retrospective research. The average age was 62. All patients underwent brachytherapy HDR or PDR procedures using a remote-after-loading system with iridium source. Results Average follow-up was 60 months. Complete remission was observed in 24 patients (72.7%) out of the whole group. Locoregional and distant recurrences were noted in 9 patients (27.3%). In all patients 5-year overall and disease free survival were 84.9% and 75.4%, respectively. The 5-year locoregional control rate was 78.8%. Conclusion Radical brachytherapy could possibly be a good treatment option in selected patients with T1-3 penile cancer and lesions smaller than 4 cm in diameter.